An Overview of C. Diff

A highly contagious "bad" gut bacteria that can cause watery diarrhea

Clostridium difficile bacteria.

Clostridioides difficile (C. diff for short) is a type of bacteria normally present in small amounts in the human gastrointestinal (GI) tract. If the balance of bacteria in your GI tract is disturbed, such as when taking antibiotics, C. diff can flourish.﻿﻿

Once it begins to take over, C.diff releases toxins that irritate the lining of the intestines. This irritation causes the main symptoms of C.diff infection: watery diarrhea and abdominal cramping.

When a person has these symptoms along with certain risk factors (such as taking antibiotics or a recent hospital stay) their doctor may suspect a diagnosis of C.diff.

The treatment for C.diff includes increasing fluid intake to prevent dehydration for diarrhea and taking antibiotics. In the rare case that the infection becomes life-threatening, surgery to remove the colon is necessary.﻿﻿

According to the Centers for Disease Control and Prevention, C. diff causes nearly half a million illnesses in the United States each year.﻿﻿


C. diff infections tend to occur when there is an imbalance of bacteria in the human gut, which allows C.diff to grow and release toxins. There are several factors that can throw off the balance of gut flora, but the one most commonly linked to C.diff infection is taking a broad-spectrum antibiotic.

These antibiotics work by targeting and killing bacteria in the intestine. The problem is, these medications don't differentiate between "bad" bacteria that make you sick and "good" bacteria that aren't harmful. Instead, all types of bacteria get wiped out.

However, C.diff can be quite hardy. What's more troubling is that certain strains are becoming increasingly resistant to antibiotics.


C. diff infections can develop during a course of antibiotics or after. The more doses a person takes, and the longer the antibiotic needs to be taken, the higher the risk of infection.﻿﻿

Research has found that several antibiotics seem to be associated with C. diff infection.﻿﻿ Potentially higher-risk antibiotics include:

  • Cleocin (clindamycin)
  • Fluoroquinolones, such as Cipro (ciprofloxacin)
  • Carbapenem-type drugs, such as Primaxin (imipenem)

Taking these antibiotics does not mean you will definitely develop a C.diff infection, as there are other factors that influence your risk. Research has shown that the risk of C.diff associated with antibiotic use is greater in hospitalized patients taking high doses of the medications.﻿﻿


C. diff is shed in feces and can be easily spread in whatever environment it's found in. Hospitals and nursing homes are common locations where C.diff can thrive.

The bacteria can live on bedrails, linens, commodes, bathroom door handles, floors, electronic rectal thermometers, and other medical equipment.

People in hospitals and long-term care facilities are more likely to be exposed to C. diff and have a higher risk of infection.

Other Factors

Research has also identified other factors that may increase the risk of C. diff infection.﻿﻿


The cardinal symptom of a C. diff infection is diarrhea, specifically loose, watery stools that occur frequently throughout the day. The diarrhea is often accompanied by abdominal cramping.﻿﻿

Other symptoms of C.diff infection may include:

  • Fever
  • Nausea
  • Loss of appetite

Complications of a C. diff infection are rare but may include:

It's fairly common to have diarrhea while (or after) taking an antibiotic. In most cases, C. diff is not the culprit. However, if you are experiencing significant diarrhea and other symptoms of the infection, call your doctor.


A C. diff infection is suspected based on a person's medical history and confirmed using one or more laboratory tests.﻿﻿

Medical History

Often, a patient's medical history is sufficient to make a doctor suspect infection with C. diff. For instance, a patient with diarrhea who is in the hospital and is taking, or has recently taken, antibiotics would prompt a doctor to test for C.diff.

Laboratory Test

A diagnosis of C. diff is usually confirmed by a positive stool test. A stool sample is needed for the test, which looks for toxins produced by C. diff (called toxin A and toxin B) as well as the gene that encodes toxin B.﻿﻿

In some cases, other tests are needed to diagnose C.diff infection. These tests require more steps, take longer, and might need to be performed at a special lab.

A doctor may want to order one of these tests to find out if someone who doesn't feel sick has C.diff—especially if the person cares for or works closely with others, such as a daycare worker or nurse.

If someone has been exposed to C.diff but doesn't have symptoms, it's still possible that they are infected and capable of spreading the illness to others (asymptomatic carrier).﻿﻿

Accurate and timely diagnosis and treatment of C.diff is not only important to helping someone manage their symptoms and reduce the risk of complications, but it's also necessary to prevent the infection's spread.


The treatment of an infection with C. diff may require multiple steps.﻿﻿ The type of treatment and its duration will depend on how severe the infection is, and a person's overall state of health.

  • Stopping the inciting antibiotic. Discontinuing antibiotic treatment may not be possible; a doctor will weigh the risks and benefits of doing so if someone is diagnosed with C.diff.
  • For hospital patients: isolation protocols. This includes wearing gloves (hand sanitizer does not kill C. diff) and gowns. Precautions are started as soon as C.diff is suspected. Since the infection spreads easily, health care workers do not have to wait for a lab test to confirm the diagnosis before taking preventative action.
  • Hydration and electrolyte replacement. Fluids can be given orally (by mouth) at home. In more severe cases, a person might need to go to the hospital for fluid replacement intravenously (through the vein).
  • Antibiotic Administration. Even though antibiotic use can lead to C.diff, certain antibiotics can be helpful in treating the infection. Most patients with C.diff can be prescribed a course of Flagyl (metronidazole), vancomycin, or Dificid (fidaxomicin). The treatment may need to be repeated if the infection doesn't get better or comes back.﻿﻿

Infection Severity

The severity of a C. diff infection varies from person to person. While most people who contract C. diff in the hospital will be treated successfully, the infection can be life-threatening for people who are immunocompromised.

In severe cases, a person with C.diff infection might need to be admitted to the hospital and kept under close medical care for days or weeks. Rarely, a person might need to have their colon removed (colectomy) if the infection has caused damage.﻿﻿


It's important to note that C. diff can reoccur—about one in five people with C. diff will get it again.﻿﻿ For a first-time recurrence of C. diff, an antibiotic regimen with oral vancomycin or oral fidaxomicin is recommended.

If someone has multiple, persistent, and severe C.diff infections, fecal microbiota transplantation (FMT) might be recommended. For FMT, stool from a healthy donor is delivered through colonoscopy or oral capsules into the gastrointestinal tract of someone who gets recurrent C. diff infections.﻿﻿


C. diff is highly contagious. However, there are precautions you can take to protect yourself if you're around someone who is sick or in an environment where C.diff is known to proliferate, such as a hospital or nursing home.﻿﻿

  • Wash your hands properly after using the bathroom and before eating. Scrub your hands and fingers thoroughly with soap and warm water for 30 to 40 seconds (the time it takes to sing the "Happy Birthday" song twice).
  • Wash any linens, clothing (especially underwear), and towels that a sick person has had contact with. Use hot water with laundry soap and chlorine bleach. 
  • Wipe down all hard surfaces in your home (light switch plates; toilet seats and flushers; oven and refrigerator handles; doorknobs; computer touchpads, etc.) with a bleach-based cleaning product. You can also mix one part bleach to 10 parts water.
  • If you are in a hospital or clinic, make sure that all health care providers are using precautions (wearing gowns and gloves) while caring for a person with C.diff.

A Word From Verywell

If you are taking an antibiotic, finished a course of antibiotics within the last month, have been in the hospital recently or are currently in the hospital and you develop diarrhea, notify your doctor. While there are many causes of diarrhea, it's important to rule out C.diff or confirm the infection as soon as possible.

Severe cases of C.diff are not common, but they can be life-threatening if they do occur. The infection can be treated and doing so will help you avoid complications, such as dehydration.

You can also prevent the infection from spreading and protect yourself from getting it by using proper hand hygiene techniques and workplace precautions if you could be exposed to C.diff at your job.

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Article Sources
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